Metal face seals have a ring like shape. Conventionally, metal face seals are polished manually and mechanically with a goal to provide a smooth surface (similar to that of a bearing). Current processes to achieve this goal include a lapping process followed by a manual or mechanical polishing process. At the end of such conventional processes, the metal face seals tend to have a circumferential or directional smoothness with substantial variability in smoothness within a single metal face seal, as well as inconsistency in a desired level of smoothness from one seal to another. Further, such circumferentiality may lead to asymmetric degradation in smoothness as the metal face seal is used in a machine, causing leaks in one direction. Furthermore, the mechanical polishing leads to a substantial loss of material of the metal face seal.
U.S. Pat. No. 8,250,757 ('757 patent) discloses laser surface treatment for mechanical seal faces. The '757 patent uses a seal ring machining equipment that has a laser unit that forms micro-topography depth features in the seal face and then performs a material surface treatment process to selectively alter the conductivity of the seal face seal face so as to virtually eliminate electro-corrosion in the seal rings. The '757 patent discloses using multiple passes of a 248 nm excimer laser for creating circumferentially spaced apart features (grooves) with variable depth in one or more directions. However, such mechanical face seals have applications different from those of metal face seals, and the circumferentiality of the polishing process has drawbacks, such as inconsistent and directional polishing of the ring surface, especially with respect to metal face seal applications.
Accordingly, there is a need to resolve these problems and other problems related to conventional methods and systems used for smoothening and polishing metal face seals.